DESTINATION MOON: A History of the
Lunar Orbiter Program
VI. ADDITIONAL READING
- This section consists of annotated
references selected by the author to give a cross-section of
information on the Lunar Orbiter spacecraft, its mission, and
lunar scientific exploration from 1961 to 1969. Many more articles
and publications about these subjects exist. However, the author
has selected these because most of them pertain to data acquired
from the five Lunar Orbiter missions. The list is intended to give
the reader a general survey of hypotheses, theories, and arguments
about the origins, the nature and the surface features of the Moon
which Lunar Orbiter has helped to uncover. It is hoped that this
will arouse the reader's curiosity to investigate the realm of
lunar sciences and exploration further.
- Adler, J. E. M., and J. W. Salisbury.
"Behavior of Water in Vacuum: Implications for "Lunar Rivers,'"
Science Vol. 164 (May 2, 1969), p. 589.
- The investigators conducted laboratory
experiments using soils with grain sizes ranging from 0 to 125
microns and gravels ranging from 2 to 4 millimeters with
gradations and layering. Tests were run under air and vacuum
conditions to determine behavior of water at various flow rates
and temperature levels on test soils. Results showed that, in
the presence of air; water formed terrestrial-like stream
channels. In a vacuum at freezing temperatures water formed
dendritic ice memo and continued to flow under the ice,
frequently penetrating to the surface and freezing. Water then
sublimated, leaving a hummocky surface. Some soil downalope
movement occurred., but no stream channels developed. Results
show that ice will readily form in a vacuum to a thickness
which allows liquid water to exist under it. Model streams
produced in a vacuum did not erode rille-like channels. Results
support, Lingenfelter's predictions (Science, Vol. 161,
- Alfven, H. "Origin of the
Moon," Science, Vol. 148
(April 23, 1965), pp. 476-477.
- There in a major implication in the
mathematical calculations of the Moon's orbit as rechecked and
improved by H. Gerstenkorn. About one billion years ago the
Moon, a separate planet orbiting the Sun, passed very close to
Earth. Both bodies continued to attract each other until the
Moon assumed a retrograde orbit about the rapidly spinning
Earth. The Moon moved within the Roche limit in a polar orbit
around Earth, causing part or the lunar surface to break away
bombard Earth. Following this the Moon began to recede from
Earth until it came to occupy its present orbit. Loosened
materials fel1 back on the Moon as meteors, making major
craters. Geological investigations might substantiate
- Allen, D., and E. P. Ney. "Lunar Thermal
Anomalies: Infrared Observations", "Science, Vol. 164
(April 25, 1969).
- Infrared observations or the Moon in
the 8- to 14-micron atmospheric window have delineated
macroscopic lunar surface thermal behavior. Shorthill has
discovered further lunar thermal anomalies. The craters
Aristarchus, Copernicus, and Tycho cool much less rapidly than
surrounding areas during eclipse. The observations made by the
authors have not determined the geometric scale of the
structure of hot and cold regions. Surface rocks in these areas
my be responsible for the less rapid cooling rates because they
are probably thermally connected to a subsurface temperature of
200 degrees Kelvin.
Norman G. Cinder Lake Crater Field Location
Test. United States Geological
Survey Interagency Report: Astrogeology 2, November 1967.
- This report describes the use of Lunar
Orbiter II photographs in conducting a test in which the
subjects were required to fix the location of a Lunar Module in
a simulated crater field near U. S. route 89, northeast of
- Baldwin, Ralph B. "Lunar Mascons: Another
Interpretation", Science, Vol. 162
(December 20, 1968) pp. 1407-1408.
- The author questions the survivability
of an impacting body. He postulates that 1) craters formed by
impacting events are dry, not lava-filled, 2) isostatic
distortions occurred, but before this was complete, lava
appeared from the body of the Moon and selectively fil1ed the
lower areas. This lava was denser than surrounding rock; which
presumably could have been more acidic, and 3) tension cracks
(rilles) and compression fractures (wrinkle ridges) show that
later subsidence and compression has occurred. Thus far only
the dense material centered in craters and capable of yielding
gravitational effects has been measured.
- The Boeing Company. Final Report on A
Study of the Lunar Orbiter Re-garding Its Adaptability to Surface
Experiments Utilizing a Fly-by and Earth-Return
Trajectory. October 6, 1966,
prepared for NASA Langley Research Center.
- This report outlines the necessary
requirements and constraints which would have to be met in
order to put a Lunar Orbiter in an Earth-return trajectory
around the far side of the Moon. This constitutes the basis of
a contingency plan, should the Orbiter have failed to go into
orbit around the Moon. During the fly-by the Orbiter could have
taken useful Photographs of the far side of the Moon. Upon
return to the Earth the spacecraft would burn its remaining
propellant to deboost into Earth orbit for readout of the
- Cambell, Malcolm J.; Brian T. O'Leary; and
Carl Sagan. "Moon: Two New Malcom Basins," Science Vol.
164 (June 13, 1969), pp. 1273-1275.
- In studying existing spherical harmonic
expansions of the Moon's
gravitational potential and the
difference among the lunar principal moments of inertia, the
authors found two large gravitational anomalies not associated
with those of Miller and Sjogren. One on the east limb of
the Moon near Mare Marginis appears to be associated with a
large circular basin, 900 kilometers in diameter, centered at
91 degrees east, 25 degrees north, with Mare Marginis filling
in the southwest corner.
- On the far side, Lunar Orbiter photos
disclose that the authors feel is an enormous circular basin
now very heavily eroded. The basin is l,000 kilometers in
diameter, centered at 173 degrees east, 11 degrees north. They
propose that this be called Occultum (Hidden Basin).
- Cameron, Winifred S. "An Interpretation of
Schroter's Valley and Other Lunar Sinuous Rilles", Journal of Geophysical Research, Vol. 69 (June 15, 1964), pp. 2423-2430.
- Various theories exist about the origin
of lunar sinuous rilles such as Schroter's Valley. The
mechanism producing them can
be categorized under aqueous
erosion, faulting, and subsidence. Each of these does not stand
the intensive investigations of the rilles' topography. Aqueous
erosion is the least tenable of all the mechanisms because it
necessitates the presence of very high vapor pressures for any
liquid at 1unar surface temperatures. Observable evidence
speaks against faulting as the major mechanism causing rilles.
Igneous processes suggest another mechanism, but, outflow of
lava creates a raised feature, not a depression. Yet one
process could explain their formation: nuses ardentes, or
fluidized outflows of gas-dust mixtures. The presence of
sinuous rilles in the vicinity of craters whose formation seems
to be volcanic strongly suggests a relationship supporting this
mechanism as the process by which these surface features have
- Cameron, Winifred S.; Paul D.
Lowman, Jr.; and John A. O'Keefe. "Lunar Ring Dikes from
Lunar Orbiter I," Science Vol. 155
(January 6, 1967), pp. 77-79.
- Lunar Orbiter I photographs reveal portions of the Flamsteed
Ring near the Surveyor
I site. The convex body
resembling a flow of viscous lava located Apollo landing site A
9.2 at 2 degrees south latitude, 43 degrees west longitude has
partially invaded nine craters in the area. This suggests that
the flow material is younger than the maze material. The
investigators conclude that these topographic features indicate
the presence of extruded intermediate lavas of acidic
composition. Such lavas are more viscous than basic lavas. The
investigators further conclude that the Flamsteed Ring in not
the result of basaltic flows despite lover gravity on the Moon.
These conclusions are preliminary.
- Conel, J. Z., and G. B. Bolstrom. "Lunar
Mascons: A Near-Surface Interpretation", Science, Vol. 162.
(December 20, 1968), pp. 1403-1404.
- The work of these two
men shows that near-surface slab-like models produce anomalies
of the magnitude, observed from tracking data of the Lunar
Orbiters. The authors assume that maria fill can be represented
by a thin circular disk of dense rock at the lunar surface,
imbedded in less dense material. Submare and adjacent rim
material has either lower density because this has been
breciated, and pulverized by impact, or is a high-density
material if brought to the impact site by an impacting
- Elston, Donald P. Character and Geologic Habitat of Potential Deposits
of Water, Carbon, and Rare Gases on the Moon. United States Geological Survey Interagency Report:
Astrogeology 6, May 1968.
- This report concerns geological
characteristics of the Moon, general composition, lunar
geological processes, and cratering by possible cometary
materials. Lunar Orbiter V photographs are used in the analysis
of craters Messier and Messier A.
- Elston, Donald P., and Charles R.
Willingham. Five-day Mission Plan to
Investigate the Geology of the Marius Hills Region of the
Moon. United States Geological
Survey Interagency Report: Astrogeology 14, April 1969.
- Lunar Orbiter V photographs H-216 and H-217 of the Marius Hills
constitute the basis for a geological survey which a manned
roving vehicle could conduct during a five-day period on the
lunar surface. Included in this report are two large geological
maps with scales of 1:200,000 and 1:25,000 respectively.
- Fielder, G., and J. E. Guest. "Lunar Ring
Structures and the Nature of the Maria", "Planetary Space Science, Vol. 16 (May 1968), pp. 665-673.
- A new interpretation of lunar ring
structures is the result of analysis of data from Lunar Orbiter
and Surveyor. Instead of accepting the hypothesis that
"elementary" rings represent old, partially filled craters, the
authors posit the hypothesis that
they are recent volcanic
structures. Elementary ring structures occur mostly on flat,
smooth floors of maria. They consist of lunaritic materials in
hills or wrinkle ridges of both. The rings approximate circles
or polygons and parts of them coincide in direction with local
tectonic patterns. The rings are generally incomplete. The
authors do not claim that all incomplete rings on the Moon have
the me origins or are of the me type.
- Filice, Alan L. "Lunar Surface Strength
Estimate from Orbiter II Photograph," Science Vol.
156.(June 16,1967), pp. 1486-1487.
- A Lunar
Orbiter II photograph of an area
in western Mare Tranquillitatis shows a boulder track down the
wall of the crater Sabine D. Assuming a spherical boulder of r=
6.5 meters and a density of 3.0
grams/centimeter3, then the
surface bearing strength in equal to 4 times
106 dyne/centimeter2 at a depth of
75 centimeters. This preliminary measurement is significant
because it can be used as a lower limit of bearing strength
over a length of 650
meters versus the footpad-sized
measurement of a landed spacecraft. The area of this
measurement is also significant because it in a potential
landing site for Apollo.
- Firsoff, V. Axel. "Water Within and Upon
the Moon", New
Scientist, Vol. 37 (March 7, 1968),
- Firsoff discusses the implications of
Lunar Orbiter photography in relation to two
main theories about the formation of lunar surface
features: water and volcanic/meteoric. The existence of sinuous
rilles, of long valleys and evidences of "aprons" to the west
and southwest of Tsiolkovsky suggest water action in various
forms from high-pressure sublimation to ash-covered glaciers.
Many formations could not have resulted from lava flows as
understood by known behavioral characteristics of such flows on
Earth. Under conditions on the Moon lava cannot travel far.
Water, however when escaping to the surface under extreme
pressure from within, could cause explosions and craters to
form. Moreover, if one assumes that Orientale, was formed in an
astroidal impact event, then this would have released
sufficient gases and meter trapped within to have formed a
temporary lunar atmosphere. The impact mould have triggered
far-reaching processes and initiated prolonged volcanic
activity whose effects would have affected the entire lunar
- Fulmer, Charles V., and Wayne A. Roberts.
"Surface Lineaments Displayed on Lunar Orbiter Pictures",
Icarus, Vol 7 ( November 1967), pp. 394-406.
- Lunar Orbiter photography reveals
closely spaced parallel lineament sets in such areas as the
craters Gambart, Maskelyne F, Gambart C, Kepler, and
Copernicus, and also in Oceanus Procellarum and in Martus.
These may be surface expressions of underlying faults or
fractures. It in not certain if these lineament sets more
restricted in formation to a single time span. Lineament sets
parallel to polygonal sides or rayed and unrayed craters
suggest the presence of a precrater parallel joint system.
These surface lineaments may have been produced by Earth tidal
forces. This would
indicate that the Moon's
surface in and has been a working unit through much of lunar
- Gambell, Neil and Baerbel K. Lucchitta.
A Limitation of First
Generation Lunar Orbiter Negatives as Applied to
United, States Geological Survey
Interagency Report: Astrogeology 11, November 1968.
- This report describes tests conducted
to determine the usefulness of Lunar Orbiter photographic
negatives in determining slopes on the Moon's surface. Random
tests were conducted to define the reliability of film density
measured against the gray scale. Results show that negatives
with density readings higher than step nine of the gray scale
give erroneous slope measurements.
- Gilvarry, J.J. "Nature of the Lunar
Mascons," Nature Vol. 221 (February 22, 1969), pp. 732-736.
- Gilvarry posits the theory that
positive and negative mascons have been caused by a series of
events after the initial formation of the Moon: The lunar seas
constitute the oldest exposed areas of the surface. Their
presence and the existence of positive and negative
gravitational anomalies in irregular maria rule out the lava
mechanism formation theory and support the theory of a lunar
hydrosphere at some time after the Moon's formation.
Experiments with various soil types under conditions involving
simulated lunar hydrosphere, atmosphere, and vacuum conditions
offer explanations for the nature of maria materials, the
former existence of surface water acting as a transport
mechanism for these materials, and the differing iostatic
conditions between maria and highland areas. Negative muscons
would have resulted when overlying water flowed to lower areas
or escaped into space. The geographical location of negative
mascons supports this supposition. Water, in turn, carried
deposits down to the great circular maria whose depths,
produced by meteoric impacts, accepted greater sedimentation
and, therefore, increased mass concentrations.
- Guest, J.E., and J. B. Murray, "Nature and
Origin of Tsiolkovsky Crater, Lunar Farside," Planetary Space Science,.Vol. 17, pp. 121-141. Oxford: Pergammon Press,
- The authors discuss the formation of
the Tsiolkovsky crater on the farside of the Moon. They base
their observations on data from Lunar Orbiter III;
high- and medium-resolution frame No. 121. Tsiolkovsky is a
landmark on the far side, a young, distinct and very large
crater in an area saturated with craters. The authors discuss
the probable origins of Tsiolkovsky in relation to: 1) the
distribution of craters around it, 2) the nature and shape of
its rim, 3) radial gouges and crater chains, and 4) the
presence of an apparent ejecta blanket. They conclude that
Tsiolkovsky formed as a result of an impacting astroidal body
or a giant volcanic explosion, and they prefer the former
hypothesis to the latter.
- Gurtler, Charles A., and Gary W.
Grew. "Micrometeoroid Hazard near Moon," Science Vol. 161
(August 2, 1968), pp. 462-464.
- All five Lunar Orbiters flew
micrometeoroid flux experiments to test the frequency of
micrometeoroid hits in the lunar environment. The only other
spacecraft which had attempt to do this was the Soviet
Luna 10. This spacecraft had registered particle
impacts exceeding by two orders of magnitude the average
of interplanetary space. The Lunar Orbiter experiments had a
configuration which detracted from maximum exposure to the
lunar environment. Test material on board each spacecraft
consisted of pressurized beryllium copper detectors covering an
area of 0.282 square meters,
of which only 0.186 square
meters was effectively exposed. Over a one year period five
Orbiters recorded a total of 22 hits or one-half
the record registered in Earth orbit by
Explorers 16 and 23, using the same
kind of detectors. The investigators caution that
these data are too tentative to form a general theory about
micrometeoroid flux near the Moon.
- Hartmanns, W. K. "Lunar Basins, Lunar
Lineaments, and the Moon's Far Side," Sky and Telescope,
Vol. 32 (September 1966), pp. 128-131.
- Hartmann has examined rectified
pictures from the Russian Zond
III of portions of the Moon's
far side and of Orientale Basin. He discusses the significance
of the pictures in theories concerning the formation of lunar
basins and the maria. Of special interest is Orientale which
involves a whole system of craters, crater chains, concentric
mountain rings and scarps including the Rook and Cordillera
mountains. Photographic data is still too scarce to determine
what role, if any, volcanism, tectonic activity, and ejected
rubble played in modifying ancient continental uplands.
- Hixon, S. B. "Topography and Geologic
Aspects of a Far-Side Lunar Crater," Science Vol. 159
(January 26, 1968), pp. 420-421.
- This brief article describes a
flow-like surface feature in a farside crater some 70
kilometers south of Tsiolkovsky. Initial analysis of Lunar
Orbiter photography indicates that the flow has a thickness of
at least 20 meters at a point about 4 kilometers east of G in
the superimposed schematic on the photograph. The author rules
out the possibilities of it being a mudflow or an air-cushioned
landslide because of vacuum conditions. He suggests that it is
considerably more like an ashflow tuff.
- Hughes, J. Kenrick, and David E. Bowker.
Lunar Orbiter Photographic Atlas of
the Moon. National Aeronautics and
Space Administration, NASA SP-206, 1971.
- A selection of photographs giving
complete coverage of the Moon, front and back, and referenced o
the surface by index map.
- Hunt, Graham R.: John W. Salisbury; and
Robert K. Vincent. "Lunar Eclipse Infrared Images and an Anomaly
of Possible Internal Origin,"Science, Vol. 162
(October 31, 1968), p. 252.
- The Authors conducted infrared studies
of the Moon in eclipse on April 13, 1968, and their
observations were the first to confirm the thermal anomalies
observed by Saari and Shorthill in December 1964. They conclude
that because, hundreds of anomalies have remained unchanged in
3.5 years, they are not the result of ephemeral
activity on the lunar surface. They detected a linear thermal
anomaly at the western edge of More Humorun which unlike
prominent crater anomalies, is warmer than its surroundings
before sunset. It remains warmer after sunset. Lunar Orbiter IV
photography of Mare Humorum, at a ground resolution of 54
meters, shows no unusual surface structures which would support
the belief that the anomaly is caused by low-thermal-inertia
material. The more probable cause is an internal heat source
because 1) beat flow to the surface would make an area warmer
than its surroundings during lunar afternoon, and
2) the geological position of the anomaly supports
- Karlstrom.. T. N. V.; J. F.
McCauley; and G. A. Swam. Preliminary Lunar Exploration Plan of the Marius
Hills Region of the Moon. United
States Geological Survey Interagency Report: Astrogeology
5, February 1968.
- The scientific objectives, operational
guidelines and surface exploration constraints of a five-day
mission of the Marius Hills constitute the subject of this
report. Lunar Orbiter
V photographs of this region
have been used in constructing preliminary geological maps and
descriptions of the traverses which astronauts could perform in
a lunar roving vehicle.
- Kosofsky, Leon J. "Topography from Lunar
Orbiter Photos," Photogrammetric
Engineering, Vol. XXXII, No.
2 (March 1966), p. 277.
- The author discusses in detail the
Lunar Orbiter photographic mission. Among its major tasks the
Orbiter spacecraft is designed to obtain useful topographical
data of the lunar surface for the Apollo Program. Special
methods of photometric data reduction not be applied to Lunar
Orbiter photography because of the peculiar characteristics of
reflectivity of the lunar surface. Preflight calibrations will
be necessary to compensate
for any distortions in
high-resolution photography due to the Moon's surface
characteristics and the fact that the film will not be returned
- Kosofsky, Leon J., and Farouk El-Baz.
The Moon as Viewed by Lunar
Orbiter. National Aeronautics and
Space Administration, NASA SP-200, 1970.
- A selected compilation of photographs
that illustrate the heterogeneous nature of the lunar surface,
including four stereographic views in color and accompanied by
index maps. Many features are similar to features or Earth;
others have no Earth counterpart. Also included are
photographic guideposts for planning manned exploration of the
- Lamar, D. L., and Jeannine McGann. "Shape
and Internal Structure of the Moon." Icarus, Vol. 5
- The authors offer a summary of the
various theories on the origins of the Moon and its shape and
internal composition. They point out that no theory has
explained the nature of the Moon's core nor the distribution of
the density of subsurface material. They do not suggest the
presence of mass concentrations (Mascons) on the Moon.
- Lamar, Donald L., and Jeannine V.
McGann-Lamar. "Shape and Internal Structure of the Moon, from
Lunar Orbiter Data". Earth Science Research Corp., Final Report,
NASA Contract NSR 05-264-002, November 1968.
- The report points out that there is a
difference between the Moon's center of figure or volume and
the center of its mass. There appears to be a systematic excess
of elevation of continental areas over maria, relative to the
Moon's center of mass.
A comparison of the mascons with
the lunar map indicates excess masses are concentrated within
the inner rings of the Imbrium and Nectare Basins. If mascons
are assumed to be masses, of nickel-iron, then they correspond
to a layer about 12 kilometers thick. Isostatic models of the
Moon also fit the date, but Lunar Orbiter data does not
sufficiently resolve which model.
- Liebelt, Paul B. "The Flight Path Control
Software System of the Lunar Orbiter," a paper presented at the
International Astronautical Federation, Seventeenth International
Astronautical Congress, Madrid, Spain, October 9-15, 1966.
- Ranger and Mariner software program
were found to be in adequate for Lunar Orbiter. Thus the Lunar
Orbiter Program developed new concepts for flight control and
the necessary software to implement them. Among other things
the optimization of the
midcourse aim point and the
orbit injection point became a necessary and practical
procedure. A man element trajectory program was developed to
facilitate orbital transfers by greatly reducing computation
times to a few minutes rather than hours as was necessary under
the special perturbation analysis approach.
- Lingenfelter, Richard E.; Stanton J.
Peale; Gerald Schubert. "Distribution or Sinuos Rilles and Water
on the Moon." Vol. 220 (December 21, 1968), pp.
- The authors present a defense of the
theory of water on the Moon as the major cause of sinuous
rilles. Their analysis is based upon data from Lunar Orbiter IV
photography and upon Urey's hypothesis of a lunar
atmosphere existing at one time in the past. They point out
that volcanic ashflows, as suggested by Gold, cannot explain
the length and meandering or many rilles. Nor can faulting.
However, waterflow under a layer of surface ice offers a viable
explanation. Moreover, certain events could. have caused
outgassing of major volatiles H20 and
CO2. Major meteor impacts would have released
trapped volatiles and could have led to a temporary
They conclude that the
distribution of sinuous rilles is the only available,
unambiguous indicator of location of subsurface
- Lingenfelter, R. E.; S. J. Peale; and G.
Schubert. "Lunar Rivers," Science, Vol. 161
(July 19, 1968), pp. 266-269.
- Lunar Orbiter photographs show sinuous
rilles resembling meandrous channels of terrestrial streams.
Thirty of these are visible from Earth. Lunar Orbiter revealed
significant new features in the smaller meandrous
channels inside the larger rilles. The authors by hypothesize
that the rilles are features caused by water erosion in
the form of ice-covered rivers whose source is
subsurface water released through the impacts of
- Lipskii, I.N. "Zond 3 Photographs of the
Moon Farside," Sky and
Telescope, Vol. 30 (December 1965), pp.
- The author describes the achievements
of Luna III in 1959 and compares them with those of the
Zond III mission in 1965 The latter confirms the data of
the former concerning the lunar far side: it is more heavily
cratered than the front side. On the whole the
craters exhibit similar features to those on the front
side. Crater chains also exist on the far side but are much
longer, in some cases 1,500 kilometers. Numerous ring-shaped
concavities called thalassoids also can be seen in
Zond III pictures. In size and shape they com pare to
maria. No such thalassoids are present on the front side.
Lipskii concludes that available data show the Moon's surface
to be continental with maria resulting from endogenic
depressions being filled with lava.
- MacDonald, Gordon J. F. "Interior of the
Moon," Science, Vol. 133
(April 7, 1961), pp.
- MacDonald discusses the several modern
theories concerning the
nature and composition of the
Moon's interior. He states that even a chemically homogeneous
Moon would undergo discontinuities in the structure of
subsurface material. Surface features and the lack of evidence
of major faulting imply a constant volume of the Moon. Little
conclusive evidence exists to prove or disprove current
The author suggested
a lunar orbiter spacecraft circling the Moon could be tracked
and that this would provide data on the Moon's gravitational
field its mean moment of inertia, and other fundamental data
which would reveal more about the
nature of the Earth's natural
- Mayo, Alton P. "Orbit Determination for
Lunar Orbiter," Journal of
Spacecraft and Rockets, Vol. 5
(April 1968), p. 395.
- This report covers the results of orbit
determination programs in the first four Orbiter missions.
Orbit determination proved to be very accurate and precise with
tolerable deviations from planned parameters. Some deviations
between planned and executed midcourse, deboost, and orbit
maneuvers resulted from oscillation in Doppler residuals,
especially in low photographic orbits. Uncertainty of lunar
gravitational constraints orbital statistics not entirely
valid. One accomplishment of the program was the improvement of
orbit determination as a result of predicted photo-location by
real-time and postflight orbit determination. On the
Lunar Orbiter III mission the difference between the two factors
was about 5 kilometers and considerably worse for certain sites
in the first two missions.
- McCauley., John F. "Geologic Results From,
the TA, Precursor Probes," a paper presented at the Fourth Annual
Meeting of the American Institute of Aeronautics and Astronautics,
October 1967. AIAA Paper No. 67-862.
- The author points out that the Lunar
Orbiter Program was by far the most productive of the precursor
probes in terms of total amount of information received and the
nature of that information in certain areas vital to further
exploration. The author discusses several of the most significant
topographical features which Lunar Orbiter photographed and
concludes that the photographic data greatly help in
identifying morphological classes of these features.
- Michael, William H., Jr., and Robert H.
Tolson. "The Lunar Orbiter Project Selenodesy Experiment," a paper
presented at the Second International Symposium on The Use of
Artificial Satellites for Geodesy, Athens, Greece., April 27-May
11, 1965. NASA/Langley Research Center.
- The authors summarize the mission of
Lunar Orbiter and concentrate upon its usefulness in the more
refined determination of the lunar gravitational field and the
Moon's shape and mass. They briefly review the existing
knowledge on these subjects and then describe in detail various
technical approaches to the problem of determining spacecraft
orbital parameters and what they will show about the
- Michael, William H.; Robert H. Tolson; and
John P. Gapcynski. "Lunar Orbiter: Tracking Data Indicate
Properties of the Moon's Gravitational Field", Science, Vol. 153
(September 2, 1966), PP. 1102-1103.
- The authors have drawn preliminary
conclusions about the significance of the orbital behavior of
Lunar Orbiter I based upon early tracking data. Their primary
task was the establishment of a rough estimate about the Moon's
gravitational field from more extensive date from the other
four Lunar Orbiter missions. Preliminary results of their
investigation show that orbital variations during periods of
photography did not degrade the quality of photographs.
Tracking data used in this analysis were two-way Doppler data
providing a measure of relative velocity of the spacecraft and
the NASA. Deep Space Network stations in California, Spain, and
- Mulholland, J. Derral, and William L.
Sjogren. "Lunar Orbiter Ranging Data: Initial Results,"
Science, Vol 155 (December 9, 1966),p. 74.
- The investigators have used ranging
residuals data from the first two Orbiter missions to test
corrections in the lunar ephemeris. Most
residuals were reduced to lose
than 100 meters. Preliminary ephemeris tapes at the Jet
Propulsion Laboratory were used to analyze raw data. Tracking
data from the Deep Space Network stations enabled the
investigators to refine the mathematical calculations.
Variations in ranging residuals from the three stations verify
unusual Doppler residuals obtained near pericenter passage of
Lunar Orbiter I. These were not attributed to onboard, system
anomalies and appeared to be real and to show that the
spacecraft had an anomalous motion of 60 meters near
- Muller, Paul M., and William L. Sjogren.
Consistency of Lunar
Orbiter Residuals with Trajectory and Local Gravity
Effects. JPL Technical Report
32-1307, September 1, 1968.
- The authors have analyzed the results
of Earth-based coherent two-way radio Doppler data from the
Lunar Orbiters. They found the residuals consistency to be too
high. This could be caused by: 1) forces such as gravity, solar
pressure, gas jets; 2) errors in tracking data; and 3) software
problems in the computer. They then utilized higher harmonics
models of the Moon, and the residuals reduced, reaching
agreement between separated flight an the saw
- Muller, Paul M., and William L. Sjogren.
"Mascons: Lunar Mass Concentrations," Science, Vol. 161
(August 16, 1968), pp. 680-684.
- The authors have constructed a
gravipotential map of the near side of the Moon based upon
orbital accelerations of the Lunar Orbiter spacecraft. These
show gravitational anomalies termed "mascons" beneath the lunar
surface in all five of the ringed maria. This suggests a
correlation between mass anomalies and the ringed maria.
Conclusions are tentative.
- National Aeronautics and Space
Administration. Lunar Orbiter I
Preliminary Results. NASA report
- A brief description of the Lunar
Orbiter Program's history, this report describes the
spacecraft, its mission, and what the first Lunar Orbiter
- Norman, Paul E. "Out-of-This-World
Engineeing, Vol. XXXV, No. 7 (July
1969), pp. 693-700.
- Norman discusses the Apollo
requirements for cartographic and topographic data on the lunar
surface., the landing sites, and their approaches.
Photogrammetry plays a mandatory role in determining accurate
coordinates for landing sites and reference marks called
landmarks. Lunar Orbiter
photographic data has provided the only applicable source for
making large-scale maps of the Apollo landing zone. How this is
done constitutes the subject of the article. The author
concludes that Lunar Orbiter successfully demonstrated the
potential of surveying and mapping the Moon or a planet from
- Oberbeck, Verne R., and William L. Quaide.
"Estimated Thickness of a Fragmental Surface layer of Oceanus
Procellarum," Journal of Geophysical
Research Vol. 72 (September 15,
1967), p. 469.
- Analyses of Lunar Orbiter I
photographs of Oceanus Procellarum showing craters of
morphology indicate a correlation between crater size and
crater shape as a result of meteorite impact against a surface
consisting of fragmental material of varying thicknesses
overlying cohesive substrata. The analysis of these data
indicate that 85% of the area considered has surface thickness
between 5 and 15 meters. Photographs from Luna 9 and
Surveyor I support this indication. Moreover, formation of
new rock surfaces appears to have occurred intermittently,
leading to a complex stratigraphic sequence of alternating hard
and fragmented rock. The existence of concentric craters
substantiates this sequence.
- Oberbeck, Verne R., and William L. Quaide.
"Genetic Implications of Lunar Regolith Thickness Variations,"
Icarus, Vol. 9 (1968), pp. 446-465.
- The distribution of the 1unar regolith
thickness for twelve areas on the Moon has been determined
using high-resolution photographs from Lunar Orbiter
II, III, and
All but one area lie within ten degrees of the equator. The
exception is in Mare Imbrium. The article compares lunar crater
geometry with laboratory craters. Results show that the
regolith thickness varied from 3.3 meters in the southern
portion of Oceanus Procellarum to 16 meters in the crater
Hipparchua. The report also discusses the delineation
of flow fronts and the discovery of many linear
markings on the presumed flows. These lineaments my be crater
chains of a collapsed or drainage origin. Still other
lineaments may be lava channels. The authors conclude that the
thickness of the regolith is a function of crater density. Over
time impacting bodies break down the lunar surface and create
the regolith which is the result of impact
- Pohn, H. A., and T. W. Offield.
Lunar Crater Morphology and Relative
Age Determination of Lunar Geological Units. United States Geological Survey Interagency
Report.7 Astrogeology 13, January 1969.
- This report describes a system for
determining the relative age of craters on the lunar surface by
using as a basis their major topographical components. From
this the authors have constructed a preliminary morphological
continuum which they use to classify craters over the entire
surface of the Moon. Lunar Orbiter photography was instrumental
in providing them with reliable data.
- Rindfleisch, Thomas. "Photometric Method
for Lunar Orbiter," Photogrametric
Engineering, Vol. XXXII (March
1966), p. 262.
- The photometric method for deriving
surface elevations from a single picture of the lunar surface
in the absence of stereoscopic pictures is described. The
author uses ganger photographs as subjects and concludes that a
derivation of quantitative topographic information about an
object scene is possible. At best the resulting data are
indirect. and estimation of errors seems unrealistic
by-analytical. means. Moreover, calculations show that it is
wrong to assume uniform albedo, for large areas.
- Rozema, Wesley. The Use of Spectral Analysis in Describing Lunar
Surface Roughness. United States
Geological Survey Interagency Report: Astrogeology 12, December
- Photography from Lunar
Orbiter III, a topographic map of the, Surveyor III
landing site, and photographs from Ranger VIII, and
are utilized in applications of the power spectral density
(PSD) function to determine relative roughness of different
types of lunar terrain. Such information would be valuable in
the construction and operation of a lunar roving
- Scherer, Lee R. "The First Four Lunar
Orbiter Photographic Missions," a paper presented to the Committee
on Space Research., London, England., July 1967.
- Scherer describes the Lunar Orbiter
spacecraft as a platform designed to carry a camera system
which can take high- and medium-resolution photographs of the
Moon's surface. The spacecraft has four objectives: 1) obtain
photography of wide areas of the Moon to certify Apollo and
Surveyor landing sites, 2) define gravitational field of the
Moon through refined tracking of the spacecraft, 3) measure
micrometeoroid and radiation flux during extended lifetime of
spacecraft, and 4) provide a spacecraft for equipment checkout
and personnel training of the Apollo tracking network.
- Stipe, J. Gordon. "Iron Meteorites as
Mascons," Science Vol. 162 (December 20, 1968) pp. 1402-1403.
- The author bases his interpretation on
studies of impacts of steel projectiles into concrete and soils
and then makes large extrapolations upward in size. On the Moon
an impacting body must penetrate below the surface to a depth
of 290 kilometers before pressure can be released sufficient to
melt material. His results suggest that lava-filled maria
formed when large iron objects struck the lunar surface at a
velocity so low that there was no immediate fracture of the
object. The impact produced a large crater and material flowed
to the surface to fill the crater. Each mare was formed by one
large iron object impacting, and the remnants of this dense
object under the mare are the mascon.
- Swann, G. A. Lunar Geological Field Investigations.
United States Geological Survey
Interagency Report: Astrogeology 9,
- Swann describes how investigation of
the Moon's surface can test the hypotheses based upon
terrestrial observations of the geological history of the Earth
in an effort to determine the origins of both bodies. The
Apollo system constitutes the basic capability with which such
extended lunar exploration can be carried out.
- Trask, N. J., and L. C. Rowan. "Lunar
Orbiter Photographs: Some Fundamental Observations,"
Science, Vol. 158 (December 22., 1967), pp.
- The first
three Lunar Orbiter spacecraft
photographed 8% (600,000 square kilometers) of the near side of
the Moon. High-resolution photographs show that the surface is
dotted with a great number of small, perfectly circular craters
from 50 meters diameter down to the limit of resolution. The
majority of these are cup-shaped with distinctly sharp rims.
But many also have shallow interiors and indistinct rims.
The authors conclude that these craters were formed by primary
and secondary impacts. Fresh craters my those which have
material on the exterior slopes which is distinctly different
from adjacent material of the inter-crater areas. These young
craters also tend to have a profusion of angular blocks on the
floors and exterior slopes. The albedo of these blocks
and other ejecta material is relatively high. The number of
fresh craters is much lose than the number of craters not
exhibiting these features.
- Tyler, G. L., et al. "Bistatic-Radar
Detection of Lunar Scattering Centers with Lunar Orbiter I,"
Science, Vol. 157 (July, 14, 1967),
- Lunar Orbiter I bounced continuous-wave signals off of the
Moon's surface, and these were received on Earth. Using the
frequency spectrum and studying Doppler shifts, the
investigators located discrete, heterogeneous scattering
centers on the lunar surface. Shadowing, especially within five
degrees of the terminator would effectively "hide" some
scattering centers. On the other hand variations in surface
reflectivity provide a model which will explain the
observations. This could mean that material in scattering areas
is considerably more compact or different from material, in
surrounding areas. The use of continuous-wave bistatic radar
appears to offer a new, method for mapping and study of lunar
and planetary surfaces.
- Ulrich, G. E. Advanced Systems Traverse Research Project
Report with a Section on Problems
for Geologic Investigations of the
Orientale Region of the Moon by R.
S. Saunders. United States Geological Survey Interagency Report:
- This two-part report discusses saw of
the problems inherent in an extended lunar surface mission in
the Orientale region and the scientific points of interest
which such a mission might best help to explore. Lunar Orbiter
photography played a significant role in the preparation of
this report. The authors discuss various arguments about the
origins of Orientale and the geological features which would be
most significant in a surface investigation.
- Urey, Harold C. "Mascone and the History
of the Moon," Science, Vol. 162
December 20, 1968), pp. 1408-1410.
- The Moon as a viscosity higher than
that of Earth by a factor of 104. Mascons
represent a non-isostatic condition in the surface of the Moon.
Apparently an object collided with the Moon's surface flattened
out and left high-density material that has remained since the
maria were formed. Lava flows cannot account for what in
observed on the Moon. Maria areas on the Moon are not lava
flows, and no liquid masses exist below the Moon. Thus large
objects collided with the Moon in its early history. These
objects should be similar to meteorites in composition and
density. Finally, the Moon has sufficient rigidity to support
- Urey, Harold C. "Water on the Moon,"
Nature Vol. 216 (December 16., 1967), pp.
- Urey summarizes several arguments
against the presence of water on the Moon, and then he presents
his own detailed argument, based upon his knowledge and new
data from Lunar Orbiter photographs, in support of the presence
of water on the Moon. The existence of rilles and of such
landmarks as Schroter's Valley, the irregularities of the
crater Krieger north of Aristarchus, and the knowledge of
terrestrial geological processes causing pingos in areas of
permafrost strongly support the theory that water has existed
on the Moon and has caused various lunar surface formations.
Urey defends the view that water, not lava or dust-gas
mixtures, formed the maria and that these may yet be frozen
seas. However, he concludes that this in no way defines the
composition of the solid materials in the maria.
- U.S. Army Topographic Command. Final
Report to National Aeronautics
and Space Administration: Convergent Stereo
Analysis. Washington, D.C.: June
- This report, done under contract to
NASA, explains the usefulness of stereoscopic photography
transmitted to Earth by Lunar
Orbiters II, III, and
in mapping the Moon. High-resolution stereo photographs include
coverage otherwise unobtainable from a vertical mode. Moreover,
the exaggerated height effects in convergent stereo photography
should increase the accuracy in the determination of ground
point elevations. The report discusses the problems of using
existing computer programs and available photographic data for
convergent photo triangulation. It also outlines the best
methods for accomplishing triangulation. Tests with Lunar
Orbiter data proved that accuracy of triangulation is increased
by using high-resolution stereo photographs.